Been working to cycle my tank for 6 mths plus after someone dumped a whole cannister of flakes in and threw it out of whack.

I've been having success in getting Nitrites & Nitrates to show up and things seem to be going well - only to one day test and they are gone! This has happened twice now and I am at a loss. Putting so much time and effort into this and my poor oscar and pleco are somehow surviving all the ammonia. What could it be that is causing the process to stop???

OK Hun... I remember the starting over thread... When this all happened...

Give me a full story. Tank size, filter, maintenance, stock list, AND WATER READINGS FOR TODAY!

Lets get this under control!

yeah me again

55 gl
1 7" albino
1 7' clown pleco

Right now all water readings are 0 because I did another massive (see: total) water change and started over last night.

Prior to that, I had steadily increasing Nitrites (1.5-2.0) and Nitrates (1.0) on two occasions for about 2 weeks - but, ammonia still steadily climbing to absurd levels (6.0-8.0). Then suddenly my friends the Nitrites were gone.

Could be that I have to do a daily water change to keep the ammonia down? Also - could it be because I used Ammo-lock?

Note: I now have 2x the filtration I used to have, added 2 HOB filters so now have enough for 100g technically...

mako22 wrote:


You know all that aside I would even go for more filtration than that if it were me... I have 800 GPH for my 55 gallon for a plec and my oscar

What type filters/ how and when do you change filter media?

the filter media is just mesh with some carbon in them - I only changed 2x in the last 5 mths, cleaned them a few times (with tank water) but everything I read said not to put new mesh in while trying to cycle...

I am at a loss here.... it should not be taking anywhere near this long to cycle...

I am going to ask a stupid question... Are you sure you are testing EXACTLY as the instructions say?

that oculd be it nicki, i thought i was getting no results on my nitrate tests untill i realised i was botching up the test, if u dont do it exactly as it says, it wont test anything...

mako22 wrote:



Hi, you say you had nitrites present but then they vanished? this is right. the nitrates will vanish once your filters start to handle them. are you still in the same position or did I read right you have done a restart????

I am hoping you haven't cleaned the filters cos i think they where about to become fully cycled(or should I say hopping). most likely reason the ammonia is so high is over feeding while you are trying to cycle the tank. feeding should be very small amounts ie once every 2 days, about 5 pellets for a full grown oscar. "Ammonia lock" will not remove the ammonia, it only binds it up to make it safe. the filter (once cycled is what will remove the ammonia.)

1 ok so you done a fully water change. did you treat the new water with a conditioner?
2 have you cleaned the filters??? please say NO
3 any chance you can post a pic of the inside of you bio filter so we can see what you have for media or give a good description. amounts/thickness/ are you using the full media supplied with the filter?
4 is the bio filters working properly. check to see the are turning?

feed very little from now on. depending on oscar size. full grown 10"+ every 2 days 5 pellets only. 6" oscar 3 pellets. below 6" 2 pellets in morning 2 at night. I can remember your last post. you cleaned all the substrate right? we will get there in the end

I am doing the testing right, definitely not that

Yes I did restart again yesterday, but did not clean the filters - just cleaned out the gravel real well (it was a mess again) 100% water change, and reduced the amount of gravel to a thin layer to avoid so much build up under there. Yes, he nitrites disappeared but there was so much ammonia I assumed the cycle didn't take as the nitrogen cycle graph always shows the ammonia levels dropping off BEFORE the nitrites do.

I think you are right, at this point the only plausible explanation is overfeeding/excess waste buildup. I've read a lot of things about vaccuuming the gravel sparingly while trying to get the cycle going but it looks like I'm going to have to keep up with it daily to keep the ammonia down. What are your thoughts on daily vigorous gravel vacs during the process?

There is nothing wrong with doing a good gravel vac every time you do a water change! Keep it to about 20-30% a day while you get your cycle complete. (we will get it complete as it is now a personal mission)

I would be careful with only doing small water changes during this time!

Thanks for taking this on as a personal mission! I will keep you posted...thanks everyone. These fish have lived through months of ammonia hoping they can hold on a little while longer until I get this figured out!

mako22 wrote:


If the filter media is only the carbon and you changed them then you will have removed all the good bacteria in the filter. This means that you will have to recycle everytime you have changed them.

What you need to do is to is not change the carbon until your filter is cycled. Then slowly change the carbon over to normal media (rock types etc)

Or if you have only just started to recycle then remove the carbon now and put the rock media in (or the hollow tubes)